The present invention relates to a plastic radiator tank for heat exchangers of internal-combustion engines, particularly for radiators of commercial vehicles, which is equipped with at least one connection tube for a heat exchange medium and which is provided with a reinforcement on its interior side.
Plastic radiator tanks of the above type are known, for example, for the radiators of the internal-combustion engine of commercial vehicles. The amount of coolant which flows through the finned-tube block of the radiators of such engines is large because the engine output to be cooled is also considerable. This also results in relatively large tanks for the radiators. The manufacturing of the tanks of a plastic material, which takes place for reasons of weight, in the case of such large engines, requires the arrangement of reinforcing parts in all areas of the tank which are subjected to high forces. In addition to the corner areas, where the side parts are fastened, this also applies to the coolant connection tube on which the hose connection must be mounted in a sealed-off manner. For this reason, it is also known to press metallic supporting sleeves into the connection tubes. However, this requires an additional operation and is therefore relatively expensive.
It is an object of the invention to provide a plastic radiator tank of the above-described type in which the subsequent pressing-in of metal sleeves becomes superfluous but that nevertheless has connection tubes with the required stiffness.
This and other objects are achieved by the present invention by providing a plastic radiator tank in which the reinforcement is formed by webs which, starting out from the interior wall, project toward the inside and which in certain embodiments are injection-molded on in one piece.
The present invention permits in a simple manner for the connection tube to be constructed correspondingly stiff already as a result of its manufacturing. Also in embodiments of the invention, it becomes possible to design the free cross-section in such a manner that the necessary coolant quantity can flow in or out. The subsequent mounting of add-on parts for the reinforcement of the connection tube is then superfluous.
There are various embodiments of web constructions which can be injection molded-on in one piece.
One embodiment comprises arranging the webs evenly distributed on the inner circumference of the connecting tube, with these webs being in the form of reinforcing ribs which extend in the flow direction.
In another advantageous embodiment, the webs are flow guiding walls which are connected with one another and preferably abut on and are connected with a hollow center piece. This results in a type of double-walled construction which is particularly stiff. It has the advantage that it is easy to manufacture and that, for a tightness test of the finished radiator, a sealing stopper can be inserted and fastened which has approximately the same structure as the core of the injection molding die that was used beforehand during the manufacturing.
It is also very advantageous, according to embodiments of the invention, to provide for circular connection tubes with the center piece being a circular-cylindrical pipe piece arranged concentrically in the free cross-section and the edges of the webs, which point toward the outside in the connection tube, being slightly set back from the front edge of the connection tube so that a circular-cylindrical sealing surface is formed which can be utilized for having a sealing stopper for the tightness test rest against it.
In other embodiments of the invention, it is advantageous, particularly in view of a required deflection of the flow through the connection tube, to arrange the center piece eccentrically in the connection tube. In certain embodiments, the webs extend radially, in the manner of spokes, or spirally, from the center of the connection tube toward the outside. However, in other embodiments, the webs are part of a honeycomb-shaped reinforcement which, in the manner of a grid, is arranged inside the free cross-section of the connection tube. For manufacturing reasons, it should be observed in all cases that the free cross-section between the webs or the center piece has walls which extend in parallel to one another, or better, widen slightly conically toward the outside so that the cores for the mold for the manufacturing of the radiator tank can be removed easily.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.